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排序方式: 共有1713条查询结果,搜索用时 15 毫秒
51.
Ethan Ponton Gustavo Turecki Corina Nagy 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2022,25(1):75
Major depressive disorder (MDD) is a common psychiatric illness that manifests in sex-influenced ways. Men and women may experience depression differently and also respond to various antidepressant treatments in sex-influenced ways. Ketamine, which is now being used as a rapid-acting antidepressant, is likely the same. To date, the majority of studies investigating treatment outcomes in MDD do not disaggregate the findings in males and females, and this is also true for ketamine. This review aims to highlight that gap by exploring pre-clinical data—at a behavioral, molecular, and structural level—and recent clinical trials. Sex hormones, particularly estrogen and progesterone, influence the response at all levels examined, and sex is therefore a critical factor to examine when looking at ketamine response. Taken together, the data show females are more sensitive to ketamine than males, and it might be possible to monitor the phase of the menstrual cycle to mitigate some risks associated with the use of ketamine for females with MDD. Based on the studies reviewed in this article, we suggest that ketamine should be administered adhering to sex-specific considerations. 相似文献
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Cianga C Cianga P Cozma L Diaconu C Carasevici E 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2004,108(2):440-444
Fas (CD95/APO-1) and its natural ligand, FasL, are molecules expressed on cellular membranes, being involved in the induction of programmed cells death or apoptosis. Recently, it has been shown that malignant cells originating from solid tumors tend to inhibit the expression of Fas, as an escape mechanism from the immune cells' attack and to express FasL, as a counterstrike mechanism against the immune effector cells. The purpose of this study was to investigate, by immunohistochemistry, the presence of Fas and FasL in 15 breast carcinomas and to establish possible associations between the expression of these molecules and the histological type and grading of the tumors. Our results showed that 7 breast tumors have lost the expression of Fas and 11 tumors were positive for the Fas-ligand expression, important arguments for the mechanisms of immune escape and tolerance induction. Furthermore, 7 of the 11 FasL+ tumors were poorly differentiated invasive ductal carcinomas, suggesting a possible association between FasL expression and tumor aggressivity. 相似文献
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Roxana Cristina Rimbaş Sorina Mihăilă Baldea Ruxandra Drăgoi Galrinho Antunes Guerra Simona Ionela Visoiu Mihai Rimbaş Corina Silvia Pop Dragoş Vinereanu 《Ultrasound in medicine & biology》2018,44(3):562-574
There are no clear recommendations regarding cirrhotic cardiomyopathy (CC) evaluation in patients with pre-transplant liver cirrhosis. The roles of new methods, tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE) in the diagnosis and prognosis of cirrhotic cardiomyopathy remain controversial. We investigated the utility of TDI/STE parameters in cirrhotic cardiomyopathy diagnosis and also in predicting mortality in patients with liver cirrhosis. Left/right ventricular function was studied using conventional TDI (velocities) and STE (strain/strain rate). We assessed left ventricular diastolic dysfunction, graded into four new classes (I/Ia/II/III). Serum NTproBNP (N-terminal prohormone of brain natriuretic peptide), troponin I, β-crosslaps, QTc interval, arterial compliance and endothelial function were measured. Liver-specific scores (Child–Pugh, MELD, MELDNa) were computed. There was a 1-y follow-up visit to determine mortality. We observed resting biventricular diastolic myocardial dysfunction, not presently included in the definition of cirrhotic cardiomyopathy. We provided an improved characterization of cardiac dysfunction in patients with liver cirrhosis. This might change the current definition. However, the utility of STE/TDI parameters in predicting long-term mortality in patients with liver cirrhosis remains controversial. 相似文献
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Corina Dota Bo Skallefell Nils Edvardsson Gunnar Fager 《Annals of noninvasive electrocardiology》2002,7(4):289-301
Background: New strategies are needed to improve the results of automatic measurement of the various parts of the ECG signal and their dynamic changes. Methods: The EClysis software processes digitally‐recorded ECGs from up to 12 leads at 500 Hz, using strictly defined algorithms to detect the PQRSTU points and to measure ECG intervals and amplitudes. Calculations are made on the averaged curve of each sampling period (beat group) or as means ± SD for beat groups, after being analyzed at the individual beat level in each lead. Resulting data sets can be exported for further statistical analyses. Using QT and R‐R measured on beat level, an individual correction for the R‐R dependence can be performed. Results: EClysis assigns PQRSTU points and intervals in a sensitive and highly reproducible manner, with coefficients of variation in ECG intervals corresponding to ca. 2 ms in the simulated ECG. In the normal ECG, the CVs are 2% for QRS, 0.8% for QT, and almost 6% for PQ intervals. EClysis highlights the increase in QT intervals and the decrease of T‐wave amplitudes during almokalant infusion versus placebo. Using the observed linear or exponential relationships to adjust QT for R‐R dependence in healthy subjects, one can eliminate this dependence almost completely by individualized correction. Conclusions: The EClysis system provides a precise and reproducible method to analyze ECGs. A.N.E. 2002;7(4):289–301 相似文献
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Brain systems mediating semantic and syntactic processing in deaf native signers: Biological invariance and modality specificity 下载免费PDF全文
Cheryl M. Capek Giordana Grossi Aaron J. Newman Susan L. McBurney David Corina Brigitte Roeder Helen J. Neville 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(21):8784-8789
Studies of written and spoken language suggest that nonidentical brain networks support semantic and syntactic processing. Event-related brain potential (ERP) studies of spoken and written languages show that semantic anomalies elicit a posterior bilateral N400, whereas syntactic anomalies elicit a left anterior negativity, followed by a broadly distributed late positivity. The present study assessed whether these ERP indicators index the activity of language systems specific for the processing of aural-oral language or if they index neural systems underlying any natural language, including sign language. The syntax of a signed language is mediated through space. Thus the question arises of whether the comprehension of a signed language requires neural systems specific for this kind of code. Deaf native users of American Sign Language (ASL) were presented signed sentences that were either correct or that contained either a semantic or a syntactic error (1 of 2 types of verb agreement errors). ASL sentences were presented at the natural rate of signing, while the electroencephalogram was recorded. As predicted on the basis of earlier studies, an N400 was elicited by semantic violations. In addition, signed syntactic violations elicited an early frontal negativity and a later posterior positivity. Crucially, the distribution of the anterior negativity varied as a function of the type of syntactic violation, suggesting a unique involvement of spatial processing in signed syntax. Together, these findings suggest that biological constraints and experience shape the development of neural systems important for language. 相似文献
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Fabio Luis-Silva Mayra Gonalves Menegueti Corina dos Reis Sepeda Bruno C. Petroski-Moraes Lucas Sato Leandro Moreira Peres Christiane Becari Anibal Basile-Filho Paulo R.B. Evora Olindo Assis Martins-Filho Maria Auxiliadora-Martins 《Medicine》2022,101(3)
Introduction:Septic shock is a lethal disease responsible for a large proportion of deaths in the Intensive Care Unit (ICU), even with therapy centered on fluid resuscitation, use of vasopressors and empirical antibiotic therapy applied within the first hour of diagnosis. Considering the multifactorial pathophysiology of septic shock and the mechanism of action of vasopressors, some patients may not respond adequately, which can lead to the maintenance of vasodilatation, hypotension and increased morbidity, and mortality. This protocol aims to verify whether the use of methylene blue in septic patients with an early diagnosis can contribute to an earlier resolution of a shock compared to standard treatment.Methods and analysis:This is a study protocol for a single-center randomized clinical trial design in an ICU of a tertiary university hospital. In this study, we intend to include 64 patients aged between 18 and 80 years with a diagnosis of septic shock, of any etiology, with up to 72 hours of evolution after volume restoration, using norepinephrine at a dose ≥0.2 μg/kg/min and vasopressin at a dose of 0.04 IU/min. After the initial approach, we will randomize patients into two groups, standard care, and standard care plus methylene blue. The sample size was calculated in order to show 30% differences in septic shock resolution between groups. The Research Ethics Committee approved the study, and all patients included will sign an informed consent form (Clinical registration: RBR-96584w4). 相似文献
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